(a) In general Except as provided in subsection (b), this subchapter and the amendments made by this suchapter shall be effective during the period beginning on and ending on .
(b) Exception With respect to any action authorized by this subchapter or information obtained pursuant to an action authorized by this subchapter, which occurred before the date on which the provisions referred to in subsection (a) cease to have effect, the provisions of this subchapter shall continue in effect.